int motor_speed                                 = 50;
int direction;
int compass_direction;
int drive_time = 600;
int relative_direction;

task display()
{
   while (true)
   {
      nxtDisplayTextLine(1,"Compass:%d",compass_direction);
      nxtDisplayTextLine(2,"Direction:%d",direction);
      nxtDisplayTextLine(3,"relative:%d",relative_direction);
      nxtDisplayTextLine(5,"Time:%d",time1(T1));
   }
}


void get_relative_direction()
{
   compass_direction = (SensorValue(S2) * 2);
   if (direction < 180)
   {
      if ((compass_direction >=0) && (compass_direction <= (direction + 180)))
      {
          relative_direction = compass_direction - direction;
       }
       else
       {
          relative_direction = ((compass_direction - 360) - direction);
       }
   }
   else if (direction >= 180)
   {
      if ((compass_direction <=359) && (compass_direction >= (direction - 180)))
      {
          relative_direction = compass_direction - direction;
       }
       else
       {
          relative_direction = ((compass_direction + 360) - direction);
       }
   }
}


void drive()
{
   get_relative_direction();
   if (relative_direction < -6)
  {
      motor[motorA] = motor_speed;
      motor[motorB] = (motor_speed /4);
      motor[motorC] = -motor_speed;
  }
  else if (relative_direction > 6)
  {
      motor[motorA] = -motor_speed;
      motor[motorB] = (motor_speed /4);
      motor[motorC] = motor_speed;
  }
  else
  {
      motor[motorA] = motor_speed;
      motor[motorB] = -motor_speed;
      motor[motorC] = motor_speed;
  }
}



task main()
{

   SensorType[S2] = sensorSONAR;
   StartTask (display);

   while (true)
   {
      PlaySound(soundBlip);
      ClearTimer(T1);
      direction = 0;
      while (time10(T1) < drive_time)
      {
         drive();
      }

...